New cycloadditions developed in our laboratories will be investigated as means to synthesize anzulenes, hydroazulenes, and sesquiterpene lactones (of potential importance as anti-tumor agents), cyclopentapyridazines (analogs of known anti-neoplastic agents which act as DNA metabolites). Experimental and theoretical studies of Diels-Alder cycloadditions to unsymmetrically substituted quinones are designed to develop understanding of the electronic and steric factors controlling regioselectivity and to develop new syntheses of anti-tumor anthraquinones. Studies of stereospecificities in alkylations are designed to provide reliable methods to predict and develop new synthetic procedures. These studies have the purposes of: (l) providing new syntheses of known chemotherapeutic agents, (2) developing novel, but general, synthetic methods based on cycloaddition, (3) production of analogs of clinically useful drugs, and (4) verifying and refining a theoretical method of predicting new cycloadditions and the regioselectivity, and reactivity in synthetically valuable cycloadditions such as the Diels-Alder reaction and l,3-dipolar cycloadditions.